Then And Now How the Cast of It's Always Sunny Aged Throughout the Show

List Rules Vote up the characters whose looks changed the most throughout the series.

Viewers weren't exactly sure what they were watching when It's Always Sunny in Philadelphia aired its first season in 2005. Since it's debut, the show has bucked all trends when it comes to TV sitcoms - even when it comes to episode titles (the show's first episode is titled "The Gang Gets Racist"). But what started as a cult TV show with a tiny viewership has grown into one of the most loved TV series of all time that has been on air for 11 seasons and counting.

Considering that It's Always Sunny has been on for 11 years, we've watched much of the cast grow from young 20-somethings to 30- and 40-somethings. Now we're taking a look back at what our favorite characters looked like in season one vs. what they look like at this point in the show. Why? Because it's fun! It's crazy to look at some of these side-by-side pictures and remember that there is an 11 year gap between them.

Fans have watched the cast of It's Always Sunny age throughout the show - from Mac's weight gain and weight loss to The Waitress's hair color change, to the real life actors all seemingly marrying each other (Day and Ellis are married to each other, as are Olson and McElhenney).

It's time to check out how the cast of It's Always Sunny aged throughout the seasons - from first gang group date to last.

During the show's seventh season in 2011, Rob McElhenney, who plays the character Mac, decided that a sudden weight gain would be a great way to mock other shows where the actors seemingly become more attractive through the seasons. He was 34 at the time. As he explained to The Wrap, "Yeah, I was jolly as f—. And I was just full of energy, because I was eating so much. It was just constant fuel." McElhenney has since taken off the weight, and grown up a bit.

Mary Elizabeth Ellis appears in the show as Waitress, Charlie's main love interest throughout the entire show. While she's a brunette at the age of 26 in the first season, her style evolves from coffee shop chic to a more sophisticated (and blonde) look.

Though she despises Charlie on the show, in real life, Ellis and Charlie Day are married. As she's said, "it’s fun when people find that out [that we're married in real life] and they’re really excited."

Danny DeVito was a fan of the show before the FX Network reached out to him to join the cast of It's Always Sunny during its second season in 2006. His character on the show, Frank Reynolds, remains the same quirky guy throughout all the following seasons.

As Kaitlin Olson said of his character and all the other characters on the show, "That's why we brought in Danny DeVito as a parent character [in season two], so we can see that this is where they're going to end up. As they get older, they'll be the same people who never learn a lesson. I love the idea that absolutely no growth has happened in these characters." DeVito has grayed a bit and his hair has gotten a little crazier as he matured through his 60s to his 70s, but not much else has changed.

As Kaitlin Olson has explained of her character Dee Reynolds, "Dee absolutely hasn't changed." She went on to say, "That's kind of the goal for us, to make sure these characters age, but don't ever grow or change. . . As they get older, they'll be the same people who never learn a lesson. I love the idea that absolutely no growth has happened in these characters." In real life, Olson and Rob McElhenney secretly began dating in 2006 when she was 31. "We were very sneaky at first because we thought, This is a really bad idea. But then I fell in love with him."